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How do type 1 diabetes mellitus and type 2 diabetes mellitus differ?
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diabetes mellitus
The islets of Langerhans are responsible for the endocrine function of the pancreas. Each islet contains beta, alpha, delta, and pancreatic polypeptide (PP) cells that are responsible for the secretion of pancreatic hormones. Beta cells secrete insulin, a well-characterized hormone that plays an important role in regulating glucose metabolism.
Type 1 and type 2 diabetes mellitus are both metabolic disorders characterized by hyperglycemia, but they differ significantly in their underlying causes and management.1
Key Differences
- Pathophysiology: Type 1 diabetes is primarily an autoimmune disorder where the pancreas fails to produce adequate insulin due to the destruction of beta cells in the islets of Langerhans. In contrast, type 2 diabetes is characterized by insulin resistance, where cells fail to respond effectively to insulin, often coupled with an eventual deficiency in insulin production.21345
- Prevalence and Risk Factors: Type 2 is much more common, accounting for approximately 90 to 95 percent of cases, and is strongly linked to obesity and lifestyle factors. Type 1 accounts for only 5 to 10 percent of cases.413
- Onset and Management: Type 1 typically begins in childhood and requires insulin injections. Type 2 generally occurs in adults—though it is increasingly seen in children—and is managed through diet, exercise, oral medications, or insulin.214
While both forms require careful medical management to prevent long-term complications, they represent distinct physiological challenges.1